fix: Fix links to editors in guide/contributing.rst. (#2217)

Links to `Sublime Text` and `Visual Studio Code` editors
were not being displayed as intended because the link
syntax was not being parsed by `sphinx` inside the boldfaced
text block.  Fix was to isolate links outside of boldfaced block.
This was tested in an alternate `sphinx` build environment
to confirm links now show up on page as intended.

An issue was not created about this.

docs/guide/contributing.rst

@@ -146,7 +146,7 @@ Create a pull request with your changes
 
           git checkout branch-name
 
-**In any text editor like `Sublime Text`_ or `Visual Studio Code`_:**
+**In any text editor like** `Sublime Text`_ **or** `Visual Studio Code`_ **:**
 
 1. Open the file you want to edit.